This proposal requests funds to continue, beyond the 32nd year, a program for training Ph.D. candidates in Cellular and Molecular Biology at the New York University School of Medicine. This program involves investigators in five basic science departments as well as Chemistry. Training is offered in the general areas of function and biogenesis of macromolecules and subcellular organelles, as well as the mechanisms that regulate cell metabolism, differentiation and growth, and intercellular interactions during development. Additions to our faculty since the last renewal application add to this program strong representation in several new areas at the cutting edge of Cell and Molecular Biology, including Cellular Immunology, Transcriptional Biology, Chemical Biology, Cellular Pathogenesis, and Disease Mechanisms. The interdisciplinary character of the program allows for a wide perspective for the student in approaching a research project and selecting thesis advisors. The design of the curriculum provides trainees with an advanced, but balanced biological education that prepares them to understand and apply to their research sophisticated ideas and methodologies of biochemistry, genetics, immunology, and molecular cell biology. The increased visibility of the research enterprise at the Medical Center, the addition of new laboratory space as well as a vigorous nationwide recruitment program has more than doubled the number of applicants to the program who are eligible for training grant support in the past decade. The program consists of lecture courses, tutorials, seminars and laboratory research and requires satisfactory performance in an oral qualifying examination. Trainees are selected from an applicant pool which is composed primarily from undergraduates or those recently graduated but employed in a research field. Candidates for admission to are selected by a committee of faculty members of the participating departments and their acceptance must be approved by the Sackler Institute, which administers all graduate programs in the Basic Medical Sciences at the School of Medicine. Students enter an open program and choose their thesis advisors and areas of research at the end of their first year and after completing three apprenticeships in different laboratories. Individual committees of faculty members follow the progress of trainees and mentor them throughout the course of their thesis research. Funds are requested to support five trainees out of a total trainee group of 30-40. Normally, four to five years will be required to obtain the Ph.D. degree. Trainees are prepared to enter fields of the biomedical sciences that have an impact on human health with respect to understanding fundamental mechanisms of Cellular and Molecular Biology as well as understanding the pathological processes such as cancer, atherosclerosis, and neurodegenerative diseases.